A screenshot of some of Silk Road's offerings, with its price marked in Bitcoins. As the crypto-currency Bitcoin has skyrocketed in value over the last weeks and then fallen even faster, it’s produced plenty of excitement and heartache for investors. But at least one Bitcoin enthusiast has been nonplussed by Bitcoin’s volatility: the entrepreneur who goes by the name the Dread Pirate Roberts, founder of the black market site Silk Road, where users can use Bitcoins to buy practically any illegal drug imaginable. In a rare (and brief) public statement sent to me, the Dread Pirate Roberts (DPR) said that despite Silk Road’s reliance on Bitcoin, commerce on the site hasn’t been seriously hurt by Bitcoin’s wild rise and fall. “Bitcoin’s foundation, its algorithms and network, don’t change with the exchange rate,” the pseudonymous site administrator writes. “It is just as import...